Bowstring release

ABSTRACT

A bowstring release having a housing with a transverse-slot in its radial wall communicating with a longitudinal bore passing therethrough. The release has an axially movable plunger in the bore which has an &#39;&#39;&#39;&#39;L&#39;&#39;&#39;&#39; shaped slot forming a nib exposed at, and coacting with the transverse-slot to retain a bowstring passing therethrough. One end of the plunger protrudes from the housing bore as a trigger a spring opposes and a screw limits motion of the plunger. The radial wall has a flat portion that supports an arrow. The transverse-slot guides a bowstring on release of an arrow.

United States Patent [191 Keeney et al.

[ 1 June 25, 1974 BOWSTRING RELEASE 1,150,038 7/1957 France 124/35 APrimary Examiner-Richard C. Pinkham Assistant ExaminerWilliam R. BrowneAttorney, Agent, or Firm-John F. McClellan, Sr.

[57 1 ABSTRACT A bowstring release having a housing with atransverse-slot in its radial wall communicating with a longitudinalbore passing therethrough. The release has an axially movable plunger inthe bore which has an L shaped slot forming a nib exposed at, andcoacting with the transverse-slot to retain a bowstring passingtherethrough. One end of the plunger protrudes from the housing bore asa trigger a spring opposes and a screw limits motion of the plunger, Theradial wall has a flat portion that supports an arrow. Thetransverse-slot guides at bowstring on release of an arrow.

15 Claims, 12 Drawing Figures PATENTEB JUHZSIBM FlGb l BOWSTRING RELEASEThis invention relates generally to projectile equip ment andspecifically to archery bowstring releases.

Longbow archery is divided into three competitive classes, epitomized bythe grip on the bowstring by which the bow is flexed and released,drawing the.

notched arrow rearward and projecting it.

In the Hunter Class the forefinger phalanx hooks around the bowstringabove the arrow and the middle and third finger phalanxes hook aroundthe bowstring below the arrow. In the Stringwalker Class, theforefinger, middle finger and third finger phalanxes hook around thebowstring below the arrow. In the Release Class a hand-manipulatedmechanism of some type draws and releases the bowstring, only one movingpart being allowed in releases in formal competition.

The Hunter Class may be said to represent the traditionalists, theStringwalker Class the progressive traditionalists, who on the averageshoot higher scores because of improved technique, and the Release Classthe relative latecomers since the class is new, who on the average shootstill higher scores.

Striking characteristics of the Release Class are that the latecomerstend to become competitive with less experience than in the otherclasses, and that the consistency of results makes more feasible the useof sighting apparatus, still further improving accuracy.

Long known aides to drawing and loosing or releasing bowstrings includefinger or thumb guards of various types and material including leatherand bone. Some of these permit one digit to hook around another whichdraws the bowstring, loosing or releasing it by relaxation of the hookeddigit.

Modern releases include the well-known loop and nail type, the rotatinghook type, and the tab type. Illustrative U.S. Pats. include Nos.3,604,407; 3,608,090; 3,656,467; 3,661,136. A plunger-releasedfrictional arrow-gripper is illustrated in French Pat. No. 1,150,038.

Reproduceability of release has within the recent past in one jumpadvanced accuracy in archery beyond anything ever before possible. v I

Comparative newcomers now routinely score higher averages than the bestconventional archers of fifteen or twenty years ago.

Learned treatises have been written on released arrow characteristics:

Arrows And Their Flight. An arrow is said to be properly matched to abow, if when well loosed, it passes the bow smoothly, without impactagainst the arrow plate,.and takes off steadily on its flight. Whenthearrow is loosed, the lateral forces upon it cause it to bend, and tobe set in oscillation about two nodal points, each approximatelyone-fifth to one-fourth the distance from the end of the shaft. Theperiod of oscillation must be so related to the time of passage of thebow that the instantaneous displacement of the part of the shaftopposite the arrow plate is outward. When this condition obtains thearrow remains clear of the bow in passing, and flies precisely in thevertical plane defined by the line of aim. An arrow that is two stiff ortoo limber oscillates either two rapidly or too slowly for propersynchronization with its time of passage, which results in its impingingon the arrow plate somewhere along the shaft, with resultant deflection.Archery, Encyclopaedia Brittanica, 1966 Ed., page 296.

The above discussion continues with a description of means of testingthe mass and stiffness or spine of arrows to determine to some degreewhich bows they will match and which not.

A principal object therefore of the present invention is to provide abowstring release which at all times and with all equipment maximizesaccuracy of arrow projection.

Another object is to provide a release as described which minimizes oreliminates bow-caused arrow oscillation.

Another object is to provide a. release as described which increasesreproduceability of release under all conditions.

And another object is to provide a release as described which gives theuser a clear sense of feel of, and sensitive control over, the relationof drawn bowstringto-release.

Still another object is to provide a release as described which givesthe user a clear sense of feel of, and sensitive control over, therelation of arrow-to-release concurrently with but separate from thebowstring-torelease feel.

Yet another object is to provide a release which is sensitivelyadjustable to suit individual release-pressure needs, and for use withvarying types and sizes of bow equipment.

A further object is to provide a release which induces the user toemploy the strongest portions of his hand for drawing the bowstring andthe less strong portions of his hand for trimming alignment andactuation of the release, and yet to aim and release with a relaxedhand.

Still a further object of the invention is to provide a releasewhich isinstantly employable at any time.

Additional objects are to provide a release as described which is easyand natural to learn to use, which is adapted for both left-hand andright-hand use, which is simple, comfortable, safe, efficient, reliable,economical, and which is attractive in appearance.

In representative embodiment given for purposes of brief summary alone,the release includes an outer elongate member having an opening, aninner elongate v member having a nib coacting with a wall of the outermember opening aligned for bowstring retention and guidance, and aplunger-type mechanism for bowstring release from the nib.

Th above objects and advantages of the invention will become morereadily apparent on examination of the following description, includingthe drawings, in which like reference numerals indicate like parts.

FIG. 1 is an isometric view of the release, with phantom linesrepresenting details of the environment of use;

FIG. 2 is a side-elevation section adapted from 22, FIG. 1;

FIGS. 3, 4 and 5 are plan sections showing three positions of operation,adapted from 3-3, FIG. 1;

FIG. 6 is a plan diagram of the invention and a bowstring portion;

FIG. 7 is a side-elevation diagram of the invention and a bowstringportion;

FIG. 8 is a rear-elevation diagram of the invention and abowstringportion;

FIG. 9 is a rear elevation;

FIG. 10 is a plan view;

FIG. 11 is a front elevation, and

FIG. 12 is an isometric exploded-assembly view.

FIG. 1 shows the release of this invention held in the hand H of anarcher drawing a bowstring B engaged in transverse slot 12 of therelease and engaging an arrow A nocked above the release, with thenocked end of the arrow resting on the release at a flat 14 .51 therelease housing or body 16. The plane of the fiat is parallel with thearrow axis.

The release lies in a horizontal plane, transverse to the bow/bowstringplane, with the long axis 18 of the generally cylindrical, tubularhousing or body of the release perpendicular to the bow. The housing issubstantially as long as the nominal hand width of the human hand. Theback of the archers hand faces upward, and his forefinger I, middlefinger II and third finger III curve downward around the body of therelease in the succession of grooves 20, 22, 24 provided. The littlefinger IV of the archer fits in groove 26 across the end of the releaseand stabilizes and trims the position of the release. All grooves areproportioned to receive nominal-size human digits.

The archers thumb V is drawn to his chin C at the limit of draw in theusual manner, following which it depresses the end or trigger portion 28of elongate plunger 30 which protrudes axially from the end of therelease, opposite the end with the groove, for the loosing the bowstringand launching the arrow.

FIG. 2, a section adapted from 2-2, FIG. 1 shows the engagement of abowstring B by nib portion 32 of circular-section plunger 30 withintransverse slot 12 in the body 16 of the release 10, and the supportiverelation of the body 16 to the rear end of an arrow A nocked on thebowstring B.

When nib 32 is axially translated on depression of plunger 30, theloosed bowstring casts the arrow. A preferred arrangement is shown inwhich the nocked end of the arrow rides against a side of the notchwhere it intersects flat 14, overlapping slightly at 34 in the viewshown. This overlapping engagement which can be felt by the archer, whocan center it by rotating the release 10 slightly, stabilizes the nockedend of the arrow along a straight edge at the instant of release. Anocking point N installed on the bowstring B just above the arrow helpsposition the arrow in the groove.

As will be seen, the release is preferably aymmetrical about thelongitudinal centerplane through the nib, and

a second flat 14 when rotated to the top permits lefthanded use of therelease in identical manner with the right-handed use described.

Preferably a relatively hard bowstring, such as the usual 12 strandDacron is used, served as at S with Nylon" monofilament to co-act withmost reproduceability with the structure of the release, both thecapitalized names being Trademarks of the E. I. DuPont de Nemours Co.

FIGS. 3, 4 and'5 respectively show in plan-section the structure of therelease 10 as it receives the bowstring B, as it retains the bowstringand as it releases the bowstring.

Plunger 30 is generally cylindrical and is constrained by the housing orbody 16 to move axially within a sliding-fit cylindrical bore 38 of thehousing or body under thumb-pressure of the user opposed by pressure ofcompression spring 40.

Length of stroke of the plunger is constant; screw 42, radially threadedthrough the wall of the body and bearing on the respective ends of axialslot 44 in theplunger, establishes the limits of travel of the plunger,and limits rotation of the plunger about the longitudinal axis.

Release pressure of the plunger is adjustably variable; plug screw 46 isaxially threaded in the bore 38 of the body 16 preloads spring asrequired to suit individual circumstances. A keeper screw 48 radiallythreaded through the wall of the housing may be used to contact and lockthe position of plug screw 46, if desired.

The combination of constant stroke and adjustable pressure permits theuser to rely on the reproduceability of release while enjoying releasepressure tailored to physical characteristics of the user.

The body 16 may be advantageously molded by polyurethane, and theplunger 30 may be formed of mild steel, preferably well polished.

Nib 32 is defined in the front periphery of plunger 30 by a generally Lshaped slot 36 penetrating to the centerline of the plunger, parallelwith the vertical center plane, leaving the nib as a cantileveredportion of the plunger periphery. The nib preferably is rounded, havingapproximately a half-thickness radius around the entire terminal portionin plan view, but, at the least around the inner face, leaving theremainder 50 of the inner face of the nib substantially parallel withthe plunger. The plunger face 52 opposite the nib lies in a radialplane.

As indicated in FIG. 3, when fully open under plunger pressure againstspring 40, the radial face 52 of slot 36 is substantially congruent witha face 54 of transverse slot 12 in the body. In plan view both slotsextend past the centerline, preferably, and verticallythrough therespective pieces. Any portion of the nib still protruding into thehousing slot at the FIG. 3 position should, as noted, present a roundedexterior, and the effective opening should be at least two bowstringdiameters wide to facilitate introducing the bowstring.

As indicated in FIG. 4, when closed in the bowstringretaining position,the bowstring is freely retained in the depth behind the nib, and theplunger preferably closes only to the point at which the end of the flatinner face 50 of the nib 32, that is, the point at which the end-radiusbegins, just reaches the centerplane of the bowstring.

The periphery P of the bowstring on the opposite side of the nib restsagainst the flat guiding face 54 of transverse slot 12 in the body, oneither side of the bore 38.

As indicated in FIG. 4, a very slight depression of the plunger 30 bythe thumb of the user causes release of the bowstring. The bowstringstabilizes on first movement by wedging outward with peripheral portionP of the bowstring bearing against the radiused end of the nib 32 whichit thrusts aside, and then continues outward, stabilizing against theradial or guiding face 54 of the transverse slot.

The initial edging action or release tends to prevent roll or twist ofthe bowstring about the axis of the bowstring, by equalizing friction onopposite sides of the circumference during the period of highest rubbingfriction.

The usual lateral oscillation of the arrow caused by side motion of thebowstring on release is prevented by the guiding and by the crisp,friction equalizing release action, withthe result that vibrationalenergy-loss is conserved and the arrow flies dead-on in the verticalsighting plane.

Elimination of lateral oscillation makes the use of plastic vanespractical under conditions in which they could not before be used inplace of feather fletching, resulting in higher velocities, lowertrajectories, and less yaw in cross winds.

In addition, the broad area of manual grip combined with the preciserelease action substantially eliminates forward creep on release,assuring uniformity of distance in successive shots.

FIG. 6 indicates in isometric plan view diagram the relatively greatlever arm L afforded the fourth or little 7 finger of the user intrimming rotation angle of the release 10 about a vertical axis at thebowstring B to square the guiding slot side 54 with the path of thebowstring. The drawing hand does not grip but is essentially relaxedsince the first three fingers hook fully about the release and generallyare called on to perform no other function than drawing.

The body end opposite the plunger end extends a distance from theplunger end nominally required to permit the human fourth finger tocrook around the end,

fitting in the end concavity 26. By slight extension or retraction ofthe fourth finger the archer adjusts the angle in the horizontal planeuntil he feels the bowstring lie flat and secure against the guidingside 54 of the transverse slot.

The archer can also feel the arrow seat itself along the guiding edge 34(FIG. 2) of the trough formed by guiding side of the slot where itintersects theflat 14 on the top of the release.

FIG. 7, a side elevation diagram of release 10 and bowstring B indicatesthat tension on the radially offset nib 32 corrects the angle ofrotation about the long axis 18 of the release. Preferably a slightdegree of rotational backlash is built into the release by making theaxial or limit slot 44 (FIG. 3) about two thousandths wider than thediameter of screw 42, increasing sensitivity of feel. The user canassure himself that the flat l4 lies along the bottom of the arrow byslightly rotating the release about the long horizontal axis, asindicated.

FIG. 8, a rear-elevation diagram of release 10 and bowstring B indicatesthat the rotational angle of the release about an axis parallel with thearrow axis is also self-corrective, and is easily felt on rotating thehand as contact pressure between the bowstring and guide surface of theslot above and below the nib.

FIGS. 9, l and 11 indicate the essential symmetry of the release aboutthe horizontal centerplane, the additional grips 20, 22', 24' 26 and theflat 14' on the opposite side making it equally useful for right-andlefthanders, and the unitary attractive appearance and damage resistant,easily-stored and quickly-deployable aspects of the invention.

FIG. 11 also shows a further preferred features of the nib 32, asymmetrical end-radius in the vertical plane, still further increasingthe sensitivity and reproduceability of release by localizing theretention of the bowstring.

FIG. 12 illustrates the economy of construction and assembly of therelease 10. The body 16, including the bore'38, transverse slot 12 andflats 14 can be molded, or machined, and the exterior can be furthershaped to suit by the individual user, employing a file and sandpaper.The plunger 30 is simply fashioned by milling and polishing a length ofsteel rod to fashion and smooth the structures of the nib 32 and limitslot 44. The trigger end 28 is preferably made slightly convex forsmoother engagement with the thumb.

The screws 42, 46 (and 48 if used) can be selftapping, or the screwholes 56, 58 and far end of the bore can be pre-threaded.

Different sizes of body or of nib 32 or of spring 40 can be substitutedby unscrewing a single screw 42.

The transverse slot 12 in the body can be made as wide as desired sincethe bowstring tends to seat automatically against the guide face of theslot, facilitating capturing the bowstring quickly and surely underadverse conditions, as in hunting. Conversely, since the releaseconveniently hangs unsupported on the bowstring without fouling, hunterscan keep hands warm in pockets until the instant of use without delay instringing the release, or in further positioning it for drawing.

Obviously, many modifications and variations of the present inventionare possible in light of the above teaching. It is, therefore, to beunderstood that within the scope of the appended claims the inventionmay be practiced otherwise than as specifically described.

What is claimed and desired to be secured by United States LettersPatent is:

1. A manual bowstring-release for use in loosing arrows, comprising: anelongated housing a means mounted in the housing for manualreciprocation to releasably hold a bowstring, said means having a nibdisposed longitudinally along one side of said means, said means havingan opening defining the nib, the nib having an end spaced from a portionof the means by said opening for receiving a bowstring therebetween, thehousing having a means positioned transversely to the opening foradmitting a bowstring to be received by the nib, and said firstmentioned means having a means free of the housing for receiving manualpressure to move the nib longitudinally so as to release a bowstringretained thereby.

2. A manual bowstring-release as recited in claim 1, means limiting thelongitudinal movement of the nib with respect to the housing, the meansin the housing having a wall longitudinally spaced from the end of thenib a distance providing for reception of said a bowstring therebetweenat one said limit of movement of the first mentioned means and forretention of a bowstring by said wall and nib at another said limit ofmovement of the first mentioned means.

3. A manual bowstring-release as recited in claim 2, said wall beingtransverse to the length of the nib, thereby providing for stabilizingguidance of a bowstring by the wall on release of a bowstring.

4. A manual bowstring-release as recited in claim 3, the housinghaving'a longitudinal exterior surface perpendicular to and intersectingsaid wall, thereby adapting an edge of the wall at said intersection forguiding a portion of an arrow when loosed by said manualbowstring-release.

5. A manual bowstring-release as recited in claim 4,

' said longitudinal exterior surface being flat, and said 7. A manualbowstring-release as recited in claim 6, wherein said portion of thefirst mentioned means is free of the housing and protrudes from an endof the housing.

8. A manual bowstring-release as recited in claim 7, wherein a resilientmember is provided within the bore of the tubular shape bearing on thefirst mentioned means thereby urging said protrusion of the firstmentioned means portion from the housing, and wherein means is providedfor adjusting the force with which the resilient member bears on thefirst mentioned means thereby adjusting pressure required for releasinga bowstring.

9. A manual bowstring-release as recited in claim 8, wherein the meansfor adjusting force of bearing of the resilient member comprises ascrew, said screw being threaded in the bore of said tubular shapedhousing.

10. A manual bowstring-release as recited in claim 9, wherein theresilient member comprises a compression spring and wherein thecompression spring bears on an end of the first mentioned means.

11. A manual bowstring-release as recited in claim 2, wherein saidopening defining the nib is L shaped, wherein the inner face of the nibis substantially parallel with the first mentioned means and hasanoutward curved portion that extends around the end of the nib.

12. A manual bowstring-release as recited in claim 1, wherein said firstmentioned means has a portion free of the housing which protrudes from afirst end of the housing, and wherein the end of the housing oppositesaid first end has a groove there across nominally sized to receive aportion of a human digit.

13. A manual bowstring-release as recited in claim 12, wherein thehousing is generally cylindrical and has a circumferential succession ofdigit grooves spaced therealong, and wherein said opening transverse tothe nib lies between two of said digit grooves proximate said first endof the housing.

14. A manual bowstring-release as recited in claim 13, wherein themanual bowstring-release is substantially symmetrical about alongitudinal centerplane passing through said nib, thereby adapting saidmanual bowstring-release for both left hand and right hand use.

manual bowstring release.

1. A manual bowstring-release for use in loosing arrows, comprising: anelongated housing a means mounted in the housing for manualreciprocation to releasably hold a bowstring, said means having a nibdisposed longitudinally along one side of said means, said means havingan opening defining the nib, the nib having an end spaced from a portionof the means by said opening for receiving a bowstring therebetween, thehousing having a means positioned transversely to the opening foradmitting a bowstring to be received by the nib, and said firstmentioned means having a means free of the housing for receiving manualpressure to move the nib longitudinally so as to release a bowstringretained thereby.
 2. A manual bowstring-release as recited in claim 1,means limiting the longitudinal movement of the nib with respect to thehousing, the means in the housing having a wall longitudinalLy spacedfrom the end of the nib a distance providing for reception of said abowstring therebetween at one said limit of movement of the firstmentioned means and for retention of a bowstring by said wall and nib atanother said limit of movement of the first mentioned means.
 3. A manualbowstring-release as recited in claim 2, said wall being transverse tothe length of the nib, thereby providing for stabilizing guidance of abowstring by the wall on release of a bowstring.
 4. A manualbowstring-release as recited in claim 3, the housing having alongitudinal exterior surface perpendicular to and intersecting saidwall, thereby adapting an edge of the wall at said intersection forguiding a portion of an arrow when loosed by said manualbowstring-release.
 5. A manual bowstring-release as recited in claim 4,said longitudinal exterior surface being flat, and said edge of the wallbeing straight.
 6. A manual bowstring-release as recited in claim 3, thehousing being tubular in shape, and the first mentioned means beingdisposed in the bore of said tubular shaped housing.
 7. A manualbowstring-release as recited in claim 6, wherein said portion of thefirst mentioned means is free of the housing and protrudes from an endof the housing.
 8. A manual bowstring-release as recited in claim 7,wherein a resilient member is provided within the bore of the tubularshape bearing on the first mentioned means thereby urging saidprotrusion of the first mentioned means portion from the housing, andwherein means is provided for adjusting the force with which theresilient member bears on the first mentioned means thereby adjustingpressure required for releasing a bowstring.
 9. A manualbowstring-release as recited in claim 8, wherein the means for adjustingforce of bearing of the resilient member comprises a screw, said screwbeing threaded in the bore of said tubular shaped housing.
 10. A manualbowstring-release as recited in claim 9, wherein the resilient membercomprises a compression spring and wherein the compression spring bearson an end of the first mentioned means.
 11. A manual bowstring-releaseas recited in claim 2, wherein said opening defining the nib is Lshaped, wherein the inner face of the nib is substantially parallel withthe first mentioned means and has an outward curved portion that extendsaround the end of the nib.
 12. A manual bowstring-release as recited inclaim 1, wherein said first mentioned means has a portion free of thehousing which protrudes from a first end of the housing, and wherein theend of the housing opposite said first end has a groove there acrossnominally sized to receive a portion of a human digit.
 13. A manualbowstring-release as recited in claim 12, wherein the housing isgenerally cylindrical and has a circumferential succession of digitgrooves spaced therealong, and wherein said opening transverse to thenib lies between two of said digit grooves proximate said first end ofthe housing.
 14. A manual bowstring-release as recited in claim 13,wherein the manual bowstring-release is substantially symmetrical abouta longitudinal centerplane passing through said nib, thereby adaptingsaid manual bowstring-release for both left hand and right hand use. 15.A manual bowstring-release as recited in claim 14, wherein said innerface of the nib extends substantially parallel with the first mentionedmeans a distance towards the end of the nib nominally sufficient tocontact the centerplane of a bowstring retained in said manual bowstringrelease.